Initial results of a phase II study of oxaliplatin (OX), capecitabine (CAP), bevacizumab (BV), and cetuximab (CET) in the treatment of metastatic colorectal cancer (mCRC).

4063 Background: FOLFOX/XELOX + BV are standard 1st line regimens for the treatment of mCRC. Based upon the activity of CET in mCRC, promising data with the XELOX-A regimen, and preclinical and early clinical data suggesting benefit from simultaneous targeting of the VEGF and EGFR pathways, we evaluated the safety and efficacy adding CET to the XELOX-A regimen. METHODS: Pts with untreated mCRC received XELOX-AE: OX 130 mg/m(2) d1, CAP 850 mg/m(2) BID d1-14, BV 7.5 mg/kg d1, and CET 250 mg/m(2) d1, 8, and 15 (loading dose CET = 400 mg/m(2)). Cycles were repeated every 3 weeks. Blood was collected for markers of response and resistance. RESULTS: 29 pts have mature data for toxicity; 24 for efficacy. Median age 56 (range 33-76). Grade 3/4 adverse events which occurred in > 10 % of patients were: diarrhea (7/29 G3) and skin rash (9/29 G3). Other events of interest were: neuropathy (21/29, 2 G3), hypomagnesemia (15/29, 3 G 3) proteinuria (3 G2), HTN (1 G1), hand-foot syndrome (1 G1, 4 G2). 17/29 pts required dose modifications (16 OX, 9 CET, 11 CAP). There were 24 pts evaluable for response, 1 CR, 10 PR, 12 SD, and 1 PD (RR=45.8%; 95% CI: 27.0%-64.6%). Median progression free survival was 10.6 months (95% CI: 7.4-16.2). Median time to progression (TTP) was 14.0 months (95% CI: 7.4-16.2). CONCLUSIONS: XELOX-AE is an active regimen in the first line treatment of metastatic colorectal cancer. However, initial RR and PFS data approximate that of treatment with CAP, OX, and BEV alone, with an increase in toxicity, mainly skin rash, hypomagnesemia, and possibly diarrhea. Patient accrual is continuing. Updated data will be presented. [Table: see text].

Duke Scholars

Author Hope Elizabeth Uronis Medicine, Medical Oncology

Author Michael Aaron Morse Medicine, Medical Oncology